CHAPTER 8: SATELLITES, SPACE STATIONS, ...& MORE!

MICROGRAVITY
Which will work better in microgravity, a pencil or a pen?
A pencil will work better, because a pen needs gravity (or another force) to push the ink to the tip.

Which will be harder to eat in microgravity--a bowl of cereal or a pop-tart? 
A bowl of cereal will be harder to eat, because gravity keeps the milk and cereal in the bowl.

How can astronauts use a treadmill for exercise in microgravity?
They need a force to replace gravity that will keep them stuck to the treadmill, usually a bungee cord.


SIMULATED GRAVITY
If you pictured a space hotel as a hockey puck that spun like a CD, would people walk on the curved part or the flat part? 
They would walk on the curved part, like they do in the movie 2001.

When the space hotel spins faster, do people feel lighter or heavier? 
They feel heavier, because more force is needed to keep them in the circle.

If you and your friend are standing on opposite sides of the space hotel, which would be closer--your heads or your feet?
Your heads!  This is backwards from our experience on Earth.


PLANETS
Which planet moves fastest around the Sun?
Mercury.  It is fastest, because it is closest.

When a planet is twice as far away from the sun, does its orbit take twice as much time? 
No.  It takes more than twice as much time.

Which planet moves in a orbit that goes above and below the plane of all the other planets? 
Pluto.  Some astronomers think Pluto might have been "captured" by the Suns gravity as it drifted by.


SATELLITES
What shape is the orbit of a satellite that travels at a constant speed-a circle or an ellipse? 
A circle.

When an elliptical satellite gets closer to the Earth, does it speed up or slow down? 
It speeds up, because of the pull of the Earths gravity.

Can a satellite orbit by hovering over the North Pole?
No.  Satellites will be pulled into the Earth unless they are moving at the right speed.  They cannot just hover in space near the Earth.


GEOSYNCHRONOUS ORBIT
If a geosynchronous satellite is over Ecuador at 06:00, where will it be at 18:00?
It will stay over Ecuador all day and all night as they both go around the axis.

If a geosynchronous satellite is over the North Pole at 06:00, where will it be at 18:00?
It will be over the South Pole, because it takes 24 hours to get all the way back to the North Pole.

What direction do all Pennsylvania satellite dishes point?
They all point toward a point over the equator; in other words, they have a southern orientation (SW--S--SE).
